How Many Types of Blood Vessels are There in The Human Body

Introduction

There are three types of blood vessels present in the human body that is Arteries which carries blood from the heart to the body , veins which carries blood to the heart from the body and Capillaries are small blood vessels which connects arteries to the veins. Basically, Blood arteries, which serve as conduits or channels, transport blood to human tissues. Two tube-like closed systems comprising the vessels start and stop at the heart. One system, the pulmonary arteries, transports blood from the right ventricle to the lungs and back to the left atrium. The secondary system that moves blood from the left ventricle to the tissues throughout the body before returning it to the right atrium is called the systemic veins.

What are blood vessels?

Blood vessels are systems of interconnected hollow pipes that transport blood to and from every area of the body. These blood veins transport blood in two directions, one from the heart to every other part of the body and the other from every part of the body to the heart.

Classification Blood Vessel

Blood vessels are categorised as arteries, capillaries, or veins based on their form and function.

Arteries

Through arteries, blood is carried away from the heart. Atherosclerotic blood from the right ventricle travels through the pulmonary arteries to the lungs. Blood that has been oxygenated by the left ventricle is delivered to the body's tissues by the systemic arteries. Large elastic arteries that pump blood from the ventricles repeatedly divide into smaller and smaller arteries, eventually leading to microscopic arteries known as arterioles. Blood flow into tissue capillaries is significantly regulated by the arterioles. The systemic arterial system contains 10% of the total blood volume at any one time.

• Characteristics of arteries

• Positioned deep within the muscle

• Possess exceptionally thick walls

• Transmit blood between the organs and the heart.

• Transfuse oxygenated blood (except for the pulmonary artery)

• Has a substantial layer of muscle tissue inside

• Acquires no valves (except for the pulmonary artery)

Structure of Artery

Three layers make up an artery's wall. The tunica intima, often referred to as tunica interna, is the innermost layer and is made up of simple squamous epithelium. It is encased in an elastic basement membrane made of connective tissue. The tunica medium, or middle layer, is frequently the thickest layer and is primarily composed of smooth muscle. To regulate blood pressure and flow, it not only supports the vessel but also changes the vessel's breadth. The outermost layer that joins the vessel to the surrounding tissue is called the tunica externa or tunica adventitia. Connective tissue that contains varying amounts of collagen and elastic fibres makes up this layer. Where it is next to the tunic media, the connective tissue in this layer is extremely dense, but it becomes loose near the vessel's periphery.

Capillaries

The arteries that remove blood from the heart and the veins that return blood to the heart are connected by capillaries, the smallest and most prevalent blood vessels (veins). Capillaries' primary function is the interchange of materials between blood and tissue cells. The metabolic activity of bodily tissues affects how capillaries are distributed.

Characteristics of Capillaries

• Are found inside every tissue

• Possess a narrow wall

• Transport blood between arteries and veins

• Conduct both oxygenated and deoxygenated blood

• Have no muscular tissue

• The total absence of valves

Structure of Capillary

Capillaries are made up of just two layers of cells and have a diameter of about 5 micrometres. Endothelial cells make up the inner layer, and epithelial cells make up the outer layer. Red blood cells must pass through them in a single file because they are so tiny.

Veins

Blood travels through veins to the heart. The smallest veins, the venules, are where blood exits the capillaries. As it enters larger and larger veins until it reaches the heart, it leaves the venules. The pulmonary circuit is the pathway via which blood travels from the lungs to the left atrium of the heart. This blood has recently been oxygenated in the lungs, which accounts for its high oxygen content. Systemic veins transport blood from biological tissue to the right atrium of the heart. This blood's oxygen content has decreased as a result of metabolic activities occurring within the tissue cells.

Characteristics of veins

• Are placed nearer your body's surface.

• The walls are thin

• Bring blood to your heart

• Carries deoxygenated blood and contains a thin layer of muscle

• Comprise valves to maintain blood flow

Structure of Veins

Veins have three layers in their walls, much like arteries do. The amount of connective tissue and smooth muscle is decreased despite the presence of all the layers. Due to the decreased pressure that blood in veins experiences compared to blood in arteries, this causes vein walls to be thinner than artery walls. Veins can hold more blood than arteries because their walls are softer and less stiff.

At any given time, the veins contain over 70% of the body's blood volume. Similar to the semilunar valves found in the heart, medium and large veins include venous valves that help maintain blood flow toward the heart. Venous valves are particularly crucial in the arms and legs because they stop blood from flowing backwards in response to gravity's pull.

Conclusion

A network of blood vessels covering more than 60,000 miles runs throughout your body. Three different blood vessel types, including arteries, veins, and capillaries, make up this remarkable circulatory system. The movement of blood throughout your body is facilitated by each in different ways. Focus on remaining active, staying hydrated, and maintaining a good diet to keep them fit and functioning.